1. Field of the Invention
The present invention relates to a compound having a polymerizability and a crystallinity, a polymer thereof and uses of the polymer. The polymer can be used for a molded article having an optical anisotropy, a liquid crystal display element and the like.
2. Description of Related Art
In recent years, a polymerizable liquid crystalline compound is utilized for a molded article having an optical anisotropy such as a polarizing plate and a phase contrast plate. This is because the above compound has an optical anisotropy in a liquid crystal state and the arrangement of the above compound is fixed by polymerization. Optical characteristics required to a molded article having an optical anisotropy are different according to the purposes, and therefore a compound having characteristics, which meets the above purpose is required. In general, the above compound is polymerized to prepare a polymer, and it is molded and utilized. In a compound used for such purpose, the characteristics of the polymer in addition to the anisotropy described above are important. These characteristics include polymerizing speed of the compound, and transparency, mechanical strength, coating property, solubility, crystallinity, shrinking property, water permeability, water absorbency, melting point, glass transition point, clearing point, chemical resistance of the polymer, and the like.
Acrylates have a large polymerization reactivity, and the resulting polymers have a high transparency, so that they are used for such purpose (refer to, for example, a patent document 1, a patent document 2, a patent document 3 and a patent document 4).    Patent document 1: JP H7-17910 A/1995    Patent document 2: JP H8-3111 A/1996 (U.S. Pat. No. 5,863,457)    Patent document 3: JP H9-316032 A/1997    Patent document 4: U.S. Pat. No. 5,622,648 are incorporated herein by reference.